Pile extractors



A. BRANDER April 18, 1961 PILE EXTRACTORS '7 Sheets- Sheet 1 Filed July23, 1957 April 18, 1961 A. BRANDER PILE EXTRACTORS 7 Sheets- Sheet 2Filed July 23, 1957 April 18, 1961 A. BRANDER PILE EXTRACTORS 7 Sheets-Sheet 3 Filed July 23, 1957 April 18, 1961 BRANDER 2,980,061

FILE EXTRACTORS Filed July 25, 1957 '7 Sheets- Sheet 4 April 18, 1961Filed July 23, 1957 A. BRANDER PILE EXTRACTORS '7 Sheets- Sheet 5 April18, 1961 Filed July 23, 1957 A. BRANDER PILE EXTRACTORS 7 Sheets- Sheet6 A. BRANDER April 18, 1961 PILE EXTRACTORS 7 Sheets- Sheet 7 Filed July23, 1957 2,980,061 PIILE EXTRACTORS Arthur Brander, Ipswich, England,assignor to The British Steel Piling Company Limited, London, England, acompany of Great Britain and Northern Ireland Filed July 23, 1957, Ser.No. 673,592 Claims priority, application Great Britain July 27, 1956 2Claims. (Cl. 121-26) This invention relates to pile extractors,primarily sheet piles, of the kind comprising a fluid pressure operatedsingle acting ram and cylinder assembly, the ram under fluid pressureapplying .an impact force to a saddle forming part of the cylinder headand thus imparting an upward tractive force to a pile held by grippingjaws positioned at the foot of the cylinder and suspended from thesaddle by a wire rope grommet extending at opposite sides and the lengthof the extractor.

Pile extractors of the kind described rely generally upon steam pressurefor their operation, the entry of steam to the cylinder being controlledby valve mechanism operable directly orindirectly by the movement of theram at a predetermined point during its stroke, the impact force appliedby the ram being invariable, an exhaust port being provided in thecylinder wall and uncovered by the ram also at a predetermined pointduring its stroke.

According to the present application a pile extractor of the kinddescribed is characterised in the provision of means whereby a variableimpact force of the ram is obtainable irrespective of steam pressuresand the stroke of the ram.

Preferably, the desired variation of impact force is obtained by theprovision of a piston valve actuated by the steam pressure available inthe ram cylinder and by-' passed therefrom through one of series ofoutlets positioned lengthwise of the cylinder and uncovered during theoperative stroke of the ram.

In order that the invention may be clearly understood and readilycarried into effect reference is directed to the accompanying drawingswherein:

Figure 1 shows in side elevation a sheet pile extractor according to theinvention.

Figure 2 is a similar view but at right angles to Figure l. V 1

Figures 3a and 3b show on an enlarged scale and in sectional elevationvalve control mechanism as fitted in a sheet pile extractor illustratedin Figures 1 and 2, Figure 3a showing the valve in the closed positionand Figure 3b showing the valve in the open position.

Figure 4 shows in side elevation a modified form of sheet pile extractoraccording to the invention, and

Figure 5 is a similar view but at right angles to Figure 4.

\Figures 6a and 6b show on an enlarged scale valve control mechanism foruse with the extractor illustrated in Figures 4 and 5, Figure 6a showingthe piston valve in its leftmost position and Figure 6b showing thepiston valve in its rightmost position.

Figure 7 shows in perspective a pair of gripping jaws forming part ofthe extractor.

Referring to the drawings which illustrate one form of sheet pileextractor constructed in accordance with the invention, the extractorcomprises a cylinder 4 closed by a bottom head 5 and a top head 6 inwhich is seated a saddle 7, the assembly being completed by a pistonUnited States atent I O exhaust port being provided at 15.

2,980,061 Patented Apr. 18, 1961 carrying a pair of dies 11 in a grip11a constituting a gripping device suspended from the saddle 7 by anendless wire cable 12 suitably protected by a rubber sleeve 13 for thegreater part of its length. The foregoing construction is substantiallyknown and consists of a single acting ram the piston imparting an impactforce into the saddle 7 upon admission of steam to the cylinder so thatan upward pull is given to the jaws through the cable connection and thesheet pile is gradually extracted from position. The piston in itsmovement uncovers an exhaust port and thereafter falls, valve mechanismbeing actuated during its movement to control the admission and cut 011of the fluid pressure, usually steam.

In accordance with the present invention the bottom head 5 houses thevalve mechanism for controlling the fluid pressure, i.e. steam throughan inlet 14, the usual The inlet of steam is controlled by a pistonvalve 16 arranged to open and close a port 17 admitting steam from anannular channel 18 to the underside of the piston 8. The piston valve isoperated by the steam presssure prevailing in the cylinder through aby-pass 19 to the underside of the piston valve 16 causing it to raiseto close off the port 17 when the piston in its upward movement hasuncovered one of a series of ports 20 in the Wall of the cylinder 4 andcommunicating with the by-pass 19 common to all.

[It will be appreciated that by this means the impact force of thepiston 8 can be controlled as the steam pressure is operative until suchtime as one of the ports 20 is uncovered by the upward movement of thepiston to by-pass steam at the same pressure tothe base of the pistonvalve 16, the piston valve having a differential cross section larger atthe base than at the top to be effective against the steam pressureprevailing in the annular channel 18 and against the upward stroke ofthe piston valve 16, The ports 20 are each closed by a removable plug 21which is available for removal by withdrawal and return of a closure 22.The impact force of the piston is increased if the uppermost plug 21 isremoved and the remaining two left in place, similarly the impact forceis decreased if the lowermost plug is removed and the remaining two leftin place. I Removal of the intermediate plug will also providefor'regulating the impact force. It will be appreciated thattwo or moreplugs 21 maybe provided and positioned lengthwise of the cylinder.

T he construction of the sheet pile extractor shown in Figures 4 and 5is substantially of the same construction of the extractor asillustrated in Figures 1 and 2 with the main exception that ahorizontally operating valve control is employed as shown in Figure 6 inplace of the vertically operating valveshown in Figure 3.

As in the previous construction, the extractor comprises a cylinder 4,bottom head 5, top head 6, saddle 7 and piston 8 (see Figure 6). The topand bottom heads are connected by bolts 9 and 10 respectively theassembly having suspended therefrom the usual dies 11 through theintermediary of a grip 11a suspended from the saddle 7 by a wire ropegrommet 12 that is to say an endless wire cable which serves as apulling link upon functioning of the extractor. The cylinder 4 andassociated parts are suspended from a crane for example by means of aneye bolt 30 connected to the head 6 by means of cables 31.

The valve for controlling the operation of the extractor is illustratedin Figure 6 and in this arrangement is horizontally disposed in thebottom head 5 which also constitutes an oil chamber 32 to which oil isintroduced through a filler 33. The valve proper 34 is slidably disposedin a valve sleeve 35 suitably fixed within the bottom edge and held inplace by a nut 36. The valve 34 is oscillatable from one extremeposition as indicated at the upper half thereof to the other extremeposition as indicated in the bottom half of the figure, thereciprocation taking place between nylon buifers 37. 14 is the usualsteam inlet from which the steam passes to the cylinder 4 through thevalve to exhaust through an exhaust port not shown but indicated as 15in Figure 3. The piston valve 34 upon reciprocation opens and closes aport 38 through which steam is admitted to an annular chamber 29 andthence through a port 40 to the cylinder 4, to raise the piston 8. Thevalve 34 is of differential cross section providing a greater pressureface as at 34a than at 34b consequently when steam admission to thecylinder takes place when the piston valve 34 is in the positionindicated in the lower half thereof the piston 8 will rise until one ofthe ports 20 is uncovered placing the bye-pass 19 in communication withthe piston valve sleeve 35 through a port 41 resulting in the pressureof steam at the greater pressure face 34a of the piston valve beingeffective to force the valve to the position shown at the upper half ofthe piston and thus shut off the steam pressure to the cylinder 8. Uponthe fall of the piston 8 after covering the port 20 previously uncoveredthe pressure in the cylinder 4- will rise to counteract the pressure atthe face 34a and as pressure increases against the pressure face 34b thepiston valve 34 will move to the position at the lower half thereof asshown in the drawing and permit steam to again enter through port 38.The operation of the valve is identical to that shown in Figure 3 Theprovision of the nylon buffers 37 at each end of the travel of thepiston valve 34 reduces chatter and the noise of the valve operation.

The oil chamber 32 (Figures 3 and 5) is vented to the cylinder through asmall passage 32a not shown in Figure 5 whereby the oil in minuteportions together with steam forming an emulsion is drawn into thecylinder upon each upward stroke of the piston and thus serving aneflective means of lubrication of the cylinder 4 and the piston 8.

Figure 7 shows in greater detail the jaws of the extractor comprising apair of dies 11 proper of wedge form supported in a grip 11a consistingof a pair of plates 11]; held together by bolts 42 the plates alsoforming a hold for the one looped end of the Wire rope grommet '12 whichforms a pulling link with the saddle 7 over which the other looped endof the grommet extends. The dies 11 are connected at each side of thegrip 11a by hair-pin springs 43 which hold the jaws 11 outwards againstramp faces 110 formed on a gapped part 11d of the grip 11a thus when anupward force is exerted on the grip 11a by an upward pull applied to thegrommet 12 upon the piston 8 striking the saddle 7 as an anvil the gripof the jaws 11 is increased and a sheet pile firmly held therebetween.The backs of the dies 11 are recessed to provide of locating the dies onthe sliding surfaces 110 of the grip 11a.

Release of the dies from the steel pile is achieved through allowing theweight of the extractor body to impact on the grip 11a thereby forcingthe grip downwards in relation to the dies which are gripping the pile.The flexibility of the wire rope sling permits this to be done. Theforce is transmitted through the fork-shaped pieces 44- (Fig. 7) whichembrace the grip. The impact may be no more than a tap or the dies mayrelease merely by the Weight of the extractor resting on the grip.

It will be appreciated that although the invention has been describedmore specifically in relation to the extraction of sheet piles theinvention is applicable to extractors for piles of all kinds, the diesand grip for instance being suitably modified. For example the extractorcan be equally well used for pulling a steel bearing pile.

What I claim and desire to secure by Letters Patent is:

1. A pile extractor comprising a cylinder, a top head and a bottom headon the cylinder, a saddle seated in the top head, means connecting thetop and bot-tom heads to the cylinder, a pile gripping means'suspendedfrom the saddle and disposed below the bottom head, a piston within thecylinder having a constant length of stroke, the cylinder having an openexhaust port adjacent the top head to exhaust the pressure operating onthe piston at the end of its stroke, a valve chamber in the bottom head,the cylinder wall having a plurality of manually controlled portsintermediate the top and bottom heads and also a by-pass thereinconnecting the manually controlled ports with the valve chamber, aninlet port in the cylinder from the valve chamber, a pressure fluidmeans connected to the bottom head and passage means connecting thevalve chamber with the pressure fluid means, valve means in the valvechamber comprising a ported valve sleeve and a valve member reciprocabletherein, the valve member having means providing on its opposite sides alarger surface area and a smaller surface area, the former beingpositioned in the valve sleeve adjacent the bypass port and the latterpositioned adjacent the inlet port thus forminga differential pressureoperated valve member, the manually controlled ports being openable byselection to allow by-passing of the pressure fluid from the cylinderthus relieving the pressure upon the piston to vary the amount of impactupon the saddle, the pressure fluid so by-passed acting on the largersurface area of the valve member to cause the valve member to move toclose otf the inlet of pressure fluid into the cylinder, the lowermostmanually controlled port when opened allowing less amount of impact andthe uppermost manually controlled port when opened allowing the highestamount of impact, the valve member being operated to open the inlet portto the cylinder by the pressure produced on the smaller surface area bythe return of the piston to the nonworking end of its stroke.

2. A pile extractor as claimed in claim 1, in which the gripping deviceis suspended from the saddle by an endless wire cable grommet whichforms a pulling link with the saddle over which a looped end of thegrommet extends.

References Cited in the file of this patent UNITED STATES PATENTS947,861 Soley Feb. 1, 1910 1,736,104 Warrington Nov. 19, 1929 2,068,045Wohlmeyer Jan. 19, 1937 FOREIGN PATENTS 345,837 Great Britain Apr. 2,1931

